Now for those that are doing comparisons with people with real hands on experience.
Here is a 1969 Stock 9.2:1 compression engine with factory open chamber heads, was a 2 barrel factory car with 727 trans and 2.94 rear gears.
Anyhow swapped on the 1406 Edelbrock 600 cfm carb with the 2 to 4 barrel adapter, so did not have to change the intake and it was still port matched to the 318 heads.
Really woke up the car by giving it more fuel, the stock 2 barrel is an economy carb and they leak gas bad so it had to come off.
The big thing that in '69 they had great compression out of the factory, and just by adding a large volume of fuel and air it added a lot of performance and with the added plus of the secondaries on the four barrel, it was a joy to drive.
Glad I did not have to tear open the 37,000 mile original engine, original car to do the 4 bbl upgrade. Still wanted to keep it as close to original as possible, it was such a cherry.